What is the SD card erase process?

user_11917350 0
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my SD card cannot work after erase, what's the matter?

  1. My SD card is working properly, then after erase 4 blocks of memory, send CMD18 it does not spit data，And the host does not get "cmd_end" MIE_EVENT。（Command transmission normal）

  2. What I'm more suspicious of is the erasure process，because of data can trans normal without erase. my erase process is： a. send "cmd32,args:start_address" b. send "cmd33,args:end_address" c. send "cmd38,args:1" start erase。

  3. The erasure process looks fine, But the evidence suggests something is wrong with it. I have looked for relevant information about SD erasure, but nothing came of it.

mmc sd-card embedded-linux
1 Answers

See the simplified SD standard, available here: https://www.sdcard.org/downloads/pls/

  • Section 4.3.5 give an overview of the erase procedure.
  • Section 4.7 details the structures of the erase commands

The SD Erase must be a aligned to and a multiple of the ERASE_SIZE. This is available from the SD_STATUS field (section 4.10.2.5). I suspect your 4 blocks are below this threshold. You should instead consider writing out the erase pattern.

user_22753320
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